Hardware 2012

3× Lithium Polymer Charger

I designed a finger-sized, low-cost charger that tops up three lithium-polymer batteries at once for about $2.50 each - built to support UCLA IEEE's OPS program instead of paying $10 for a single charger.

PCB Design
Power Electronics
Battery Charging

fig.17 - The finger-sized 3× lithium polymer charger PCB

I designed the 3× lithium polymer charger as a low-cost way for students to charge their batteries, specifically to support the OPS program. It charges three batteries at once and costs roughly $2.50 per charger (with a power supply), against $10 for a single charger at SparkFun.

Each battery charges at a maximum rate of 500 mA and has an individual status indicator that shows when the battery is fully charged.

Schematic

Charger schematic

Board

Charger PCB layout